Heat treating of articles



G. H. GILMAN HEAT TREATING OF ARTICLES Filed Sept. 4, 1920 4 Sheets-Sheet 2 lzwenior: fleorge If. Gz'bnan,

Reba 2 1926.. 1,571,329

G. H. GILMAN HEAT TREATING OF ARTICLES Filed Sept. 4, 1920 4 Sheets-Sheet 5 n; rave-2220? aeorge lziiiman bydiuz M u i i'ys.

Feb, 2 1926.

G. H. GILMAN HEAT TREATING OF ARTICLES Filed Sept. 4:, 1920 4 Sheets-Sheet 4 UNITED] STATES 1,571,329 PATENT OFFICE.

GEORGE H. GILMAN, OF BOSTON, MASSACHUSETTS.

HEAT TREATING OF ARTICLES.

Application filed September 4, 1920. Serial No. 408,283.

To (ZZZ whom it may concern:

Be it-known that I, GEORGE H. GILMAN,

a citizen of the United States, and a resident of Boston, county of Suffolk, State of Massachusetts, have invented an Improvement in Heat Treating of Articles, of which the following description, in connection with the accompanying drawings, is a specification, like characters on the drawings representing like parts.

My invention relates to methods of and apparatuses for heat treating articles and while applicable in respect to many of its features to the heat treatment of articles in general, it is particularly adapted to the heat treatment of the stecls used for rock drilling. I

' My invention will be best understood by reference to the following description of one embodiment of my invention submitted for illustrative purposes, when read in connection with the accompanying drawings, while its scope will be more particularly pointed out in the appended claims.

Figure 1 is a sectional elevation on the line 11 of Fig. 2, and showing an apparatus for heat treating drill steels;

Fig. 2 is a-plan view of the apparatus shown by Fig. 1;

Fig. 3 is a-- diagranrillustrating the operation of my invention as embodied in the apparatus illustrated by Figs. 1 and 2;

Fig. 4 is a plan view of the furnace;

Fig. 5 is a sectional development on the line 5-5 of Fig. 1; y l

Fig. 6 is a section on the line 66 of Fig. i; and 1 Fig. 7 is a section on the line 77 of Fig. 2.

Referring to Fig. 3 of the drawings, which illustrates diagrammatically the operation of an apparatus and the steps of a method of treating a drill steel, which apparatus and method constitute the embodiment I have selected for illustrating my invention, 1 haveshown a furnace 1 and a quench ng tank 2, through. which-the portions of the drill steel 3 to be treated are'passed. These drill steels are detachably connected to car 'rie'rs 4 provided with wheels 5. which roll along an undulating track 6, the] carriers being moved at a continuous uniform speed by means of suitable pusher elements-7. In a manner to be more fully described, the drill steel is-first placed with the end'to be treated on a suitable loading platform 8 and then is attached to the carrier. The platform in this way acts as a gauge to cause the drill steel to project the requisite distance below the carrier, which distance is dependent on the height of the table 8. The carrier is now moved along the straight portion 9 of the track, until it reaches the downwardly inclined portion 10, when the drill steel is lowered into the furnace. The drill steel now continues to move at a uniform speed along the straight portion 11,0f the track above the furnace and the end of the steel is heated. After the drill steel passes out of the furnace, the carrier follows the downwardly inclined portion 12 of the track, which lowers the extreme cutting end of the drill steel into the quenching tank 2, the latter being filled to the requisite level with a suitable quenching fluid such as oil, or water,

preferably the latter. This fluid is admitted When the carrier reaches the end of the tank, it follows the upwardly inclined portion 15 of the track, which raises the drill steel out of the quenching fluid, and when the carrier, then following the straight portlon 16 of the track, reaches the disengaging cams 17, the drill steel is automatically disengaged from the carrier.

As will hereinafterwards be more fully pointed out, the furnace is so constructed in the submitted embodiment of my invention to provide a slot 18 in communication with a combustion chamber. It is further provided with a suction discharge opening 19, which causes the products of combustion to be drawn through the slot 18 as indicated by the arrows 20, which directs them against the portion of the drillsteel below the slot 18. "Through the opening 21 of the furnace, which has a width slightly greater than the diameter of the drill steel is sucked a draft of air, which, as indicated by the arrows 22, blows against'the portion of the drill confined to the end'portion thereof extendinto the furnace, of course, all

-ing into the furnace as shown by Fig. 1.

The products of combustion and air drawn ass out of the furnace by Way of the discharge 19.

It will be understood that it is of considerable importance to have the extreme cutting end of the drill steel extremely hard and the portion in back of the cutting. edge tough in order to prevent breaking of the end of the steel, which would occur if the degree of hardness at the cutting end extended back a considerable distancefrom the end. For this purpose, only the cutting 'end is immersed in the quenching medium 'as the drill steel passes over the straight portion of the track 13 above the tank, which chills and hardens the extreme end, while the drill steel is relatively hot. This action is accentuated by causing the cold quenching fluid to be projected against the steel at this portion of its travel. When the carrier reaches the portion of the track 14 above the tank and the drill steel is cooled to some extent, the drill steel is gradually lowered into the quenching fluid and the. portion behind the cutting edge is thus gradually cooled, which results in the hardness gradually decreasing as the material recedes from the cutting edge, causing an extremely tough backing for the latter.

Referring to Figs. 1 and 2 I have shown the track 6 as circular and supported by suitable brackets 23 from a table 24. The furnace and tank are made arcuate to conform with the track. The carrier 4 I have shown in the form of a U-shaped member provided with the legs 25 and 26,- the legs 26 carrying the wheels 5 which support the carrier on the track. For detachably securmg the drill steel to the carrier I have shown conventional gripping devices or spring cllps 26 which may be constructed in any suitable manner as for exam le as shown in my copending application erial No. 350,- 434, filed January 9, 1920, it being understood that the operator manually places the end of the drill steel on theplatform 8 and pushes thesteel into engagement with the grlpping devices 26 as the carrier passes over the platform as' illustrated in Fig. 2.

For moving the carriers I have shown supported in suitable bearings carried by the table 24, the shaft 27, the shaft being provided with a worm wheel 28 in engagement with a worm 29 rotated by the electric motor 30. This drives the shaft at a uniform speed. Secured to the upper end of the shaft is a member having the hub portion 31 and the radial arms 32, the ends of the arms being provided with the pusher elements 7 which comprise the side members rier.

33 adapted to embrace the leg 26 of the .car-

In an obvious manner, when the pusher elements are rotated, the carrier is pushed around the track, the leg 26 of the carrier sliding between the side members 33 of the pusher elements to compensate for the undulations of the track.

' For disengaging the steel from the carrier I have shown the cams 17 carried by a suitable standard 34. In an obvious manner as illustrated by Fig. 2, asthe carrier moves towards the cams, the ends of the latter enter the space between the drill steel and the leg 25 of the carrier, and the steel traveling along the surface of the cam causes the steel to be pulled out of the gripping devices 26. I

The details of the furnace are illustrated by Figs. 4, 5 and 6. Referring to these figures, I have shown a casting 35 which forms a casing for the furnace structure, the walls of the latter being made of a refractory material. In the upper portion of the furnace I have shown a pair of combustion chambers 36, into which is projected a flame from suitable oil burners 37. Between the combustion chambers I locate a heating chamber 38 which communicates with the exterior of the furnace through an arcuate slot 39 formed in the cover 40 of the furnace and through a slot L7 in the end of the furnace, while connecting i the chambers with the heating chamber I have shown a pair of slots 18 extending substantially the length of the heating chamber. For closing the end slots .1 may provide a door 48 carried by hinges 49 and normally held in closed position by the cam 50 and coacting weighted lever 51. As will be obvious this door is adapted to be pushed open by the steel and to close automatically when the steel passes out of the furnace. The lower surface of the heating chamber extends downwardly as shown at 41', to increase the volume of the chamberas the discharge opening 19 is approached. This discharge opening communicates with a stack 42 provided with suitable draft producing apparatus such as an injector nozzle 43 which causes the pressure in the heating chamber to be lower than that of the atmosphere. This difference in )ressure causes the flame and the products of combustion to pass from the combustion chambers through the slots .18 into the heating chamber and thence to the stack, and in their passage to play against the portion of the drill steel projecting below the slots. To facilitate this action, thelower portion of the cover ll) and the upper surface of the walls 4-4, separating combustion the combustion chambers from the heating chamber are so formed, as illustrated by Fig. 6, as to cause the flame to be projected downwardly. This difference in pressure also causes air as indicated by the arrows 22 andfurther the air passing into the furnace through the slot 39 is caused to flow against the drill steel. which keeps the portion thereof above the slot cool and thus localizes the heated portion of the steel. It will be noted that by these means not only will the products of combustion be prevented from escaping from the furnace through the openlngs provided to recelve the article being heated, but that the portion thereof heated may be regulated to a nicety by adjusting the height of the loading platform relative to the furnace and track.

' This application claims a species of the invention more broadly claimed in applicants copending application Serial No. 350,-v

' 436, filed January 9, 1920.

While I have shown herein and described for purposes of illustration one specific embodiment of my invention, it is to be understood that the invention is not limited to this embodiment but that wide deviations may bemade therefrom without departing. from the spirit of my invention.

I claim: T

1. In a heat treating apparatus, means for localizing the heated portions of heat treated articles by applying heat to such portions and subjecting the contiguous, portions thereof to a flow of relatively cool medium, and means for moving said articles during such heating operation.

2. In a heat treating apparatus, means for localizing the heated portions'of heat treated articles by applying heat to such portions and subjecting the contiguous portions thereof toa draft of relatively cold air, and

means for moving said articles during such heating operation.

3. In a heat treating apparatus, means for localizing the heated portions of heat treated articles by applying a hot fluid to such portions and sub ecting the contiguous portions to a flow of cold fluid,'and means for moving said articles during such heat-- lng operation.

4-. In a heat treating apparatus, means for localizing the heated portions of heat treated articles by applying hot products of combustion to such portions and subjecting the contiguous portionsto a flow of cold fluid,-

and means for moving said articles during such heating operation.

5. The method of heat treating a drill steel which comprises subjecting one portion of the steel toheat for heating it, simultaneously subjecting the contiguous portion to a flow of cold medium, and afterwards quenching thev heated portion.

6. In a heat treating machine for drill steels, means for heating the end portions 'ing the portion of said steels adjacent said end portion to a draft of cold air, and means causing said steels to be subjected to said heating 'for apredetermine'd period.

8. The method of 'heat treating the end portion of a drill steel which comprises heating such end by the application of heat,

localizing the heated portion by the application of a flow of cold medium, quenching the extreme end until it is hardened, and afterwards quenching the remaining heated portion.

9. The method of heat treating a drill steel which comprises subjecting one portion thereof to heat, simultaneously subjecting the contiguous portion to a draft of cold air, and afterwards quenching the heated portion.

10. The method of heat treating the cutting end of a drill steel which comprises heating the cutting portion and the portion adjacent thereto by the application of hot products of combustion and simultaneously subjecting the part adjacent to the heatedportion to a draft of cold air, afterwards quenching the cutting portion only, and finally progressively quenching the remainder of the heated portion.

11. The method of heat treating the cutting end of a drill steel which, comprises heating the end portion of thesteel, quenching the cutting end by projecting thereagainst a quenching fluid, and finally quenching the remaining portion of such heated end. I

12. The method of heat treating the cutting end of a drill steel which comprises heating the end portion of the steel, quenching the cutting end by projecting thereagainst a quenching fluid, and finally progrcssively quenching the remaining portion of such heated end.

13. In a heat treating apparatus, the combination With means for heating the article to be treated, of a quenching tank, means for passing such article throughsaid tank comprising a continuously moving carrier bination with means for heating the article to be treated, of a quenching tank, means for passing such article through said tank comprising a continuously moving carrier for said article arranged to subject only a fixed predetermined portion of said article to the quenching medium for a fraction of the travel and progressively to subject the remaining heated portion of said article to said medium for other fractions of its travel.

15. In a heat treating apparatus, the combination with means for heating the article to be treated, of a quenching tank, means for passing such article through said. tank comprising a track and a continuously moving carrier for said article, said track being arranged to subject only a fixed predetermined portion of said article to the quenching medium for a fraction of the travel and to subject such portion and other portions to the quenching medium for other fractions of its travel.

16. In a heat treating apparatus, the combination with means for heatin the article to be treated, of a quenching tan means for passing such article through said tank comprising a track and a continuously movng carrier for said article, said track being arranged to subject only a fixed predeter: mined portion of said article to the quenching medium for a fraction of the travel and progressively to subject the remaining heated portion of said article to said medium for other fractions of its travel.

17. In a heat treating apparatus, the combination of means for heating the article to be treated, of means for subjecting said article to a quenching medium comprising a continuously moving carrier for said article, said means being arranged to subject only a fixed predetermined portion of said article to said medium for a fraction of the travel and other portions during it remaining fraction of the travel.

18. In a heat treating apparatus, the combination of means for heating'the article to be treated, of means for subjecting said article to a quenching mediumcomprising a continuously moving carrier for said article, said means being arranged to subject only a fixed predetermined portion of said article to said medium for a fraction of the travel and progressively tosubject to said medium other portions of said article during a remaining fraction of the travel.

1!). In a heat treating apparatus, means tguiheating the end of an article to be treate' l,' ineai1s for projecting a quenching medlum against a portion of the heated por- (ion of said article. :ind means for afterwards quenching the remainder of said heat d Portion.

20. In a heat treating apparatus, means for heati'ngthe end of an article to be treat ed, and-means for cooling a portion of the heated end of said article by projecting thcrcagainsta quenching medium.

21. In an apparatus for heat treating drill steels, means for heating the end of a steel, and means for afterwards projecting a quenching medium against the end of said steel.

7 22. In an apparatus for heat treating drill steels, means for heating the end of a steel, means for afterwards projecting a quenching medium against the end of said steel, and mcansfor finally progressively subjecting the remaining heated portion of said end to a quenching medium.

23. In a heat treating apparatus, means for projecting a quenching medium against a part of the heated portion of an article, and means for afterwards quenching the remainder of said heated portion.

24. In a heat treating apparatus for drill steels, means for heating an end of a steel, means for projecting a substance against said end while heated for causing hardening of said end, and means for finally quenching said end.

25. In a heat treating apparatus for drill steels, means for heating an end of a steel, means for projecting a liquid substance against said end while heated for causing hardening of said end, and means for finally quenching said end.

26. In a heat treating apparatus for drill steels, a quenching tank, means forming an inlet for said tank and providing a zone through which the quenching liquid is projected, and means for moving a previously heated portion of a steel through said Zone to subject it to said projected quenching fluid.

27. In a heat treating apparatus for drill steels, a quenching tank, an inlet for said tank comprising a pipe having an extended outlet, and means for moving the tip of a previously heated drill steel in the direction of extent of said outlet to subject said steel to the discharge of said outlet.

28. In a furnace, a combustion chamber, a chamber having an opening for the insertion into said chamber of an article to be heat ed, a connection between said chambers, and means for causing a flow of air through said opening.

29. In a furnace, a chamber for a heating medium, said chamber having an opening through a wall thereo'f'for the insertion of an article to be heated, and means for forcing a. flow of air through said opening into said chamber, whereby to keep cool the portion of such article exterior to said chamber.

30. In an apparatus for heating articles, a chamber for a heating medium into which ,medium a portion of such an article is adapted to be inserted. and means for causing a flo'w'of cold medium against the portion of said article contiguous the heated portion. V 1

31. In a furnace, a combustion chamber,

llo

a flue chamber, a connection between said chamber and flue, sald flue chamber havmg a wall provided with an opening through tween said chambers arranged to direct products of combustion against said article adjacent its point of insertion into said flue chamber, and. a discharge opening for said flue chamber causing said products of com,- bustion to flow lengthwise of said article toward its end. I

33. In a furnace,a combustion chamber, a flue chamber, means providing for the insertion into said flue chamber. of an article .to be heated, a connection between said chambers arranged to direct products of combustion against said article, and means to cause a flow of air against the portion of the article exterior to said chamber.

34. In a furnace, a heating chamber having a wall provided with an opening for the insertionof an article to be heated, said opening hem of large cross-sectional area relative to said article, and means for causing a pressure in said chamber below that of the surrounding environment, wherebyto prevent the escape of heated medium from said chamber.

35. In a furnace, a chamber containing a heating medium, a cover for said chamber having an elongated opening through which the article to be heated is adapted to be inserted and caused to travel along said opening from one portion of said chamber to the other, and means for causing a flow of air through said opening into said chamber.

36. In a furnace, a chamber containing a heating medium, a cover for said chamber having an elongated opening through which I the article to be heated is adapted to be inserted and caused to travel along said opening from one portion of said chamber to the other, and means for subjecting the portion of said article contiguous to that heated to a flow of cold medium.

37. In a heat treating apparatus, a fur-- nace having an opening for the insertion of an article and an opening for the removal of 'said article, one of said openings being arranged to permit the insertion by a movement lengthwise of the article and the other to' 'permit its removal by a movement sideways of the. article, and a door for closing the last named opening.

38. In a furnace, an opening through the wall of said furnace along which an article is adapted to travel after its insertion, and

a door normally closing the end of said opening and mounted to be pushed open by said article to permit its removal.

39. In a furnace, means forming a chamber into which a drill steel or the like is adapted to be inserted and caused to travel lengthwise of said chamber, a flue for conducting heated gases arranged parallel to said chamber, and a slot extending substantially the length of said chamber for placi lng the latter in communication with said gated chamber into which drill steels or the like maybe inserted, a slot formed in the wall of said chamber transverse to said drill steel and extending substantially the length of said chamber adjacent the point of insertion of said. drill steel, and means for passing hot products of combustion into said chamber through said slot.

41. In a furnace, means forming an elongated chamber into which drill steels or the like may be inserted, means for passing hot products of combustion into said cham-' her in the form of a substantially uninter- 40. In a furnace, means forming an elonrupted sheet along the length thereof, and

for causing said products after entering said chamber to travel lengthwise of said steels and along said chamber and to be discharged'therefrom at one end thereof.

42. In a furnace for drill steels or the, like, a chamber, means for inserting the end of a steel into said chamber and for moving 'it lengthwise of said chamber, and means for passing hot products of combustion into said chamber along the line of'travel of said steel and for causing said products of combustion to travel lengthwise of .the steel toward its end.

43. In a furnace for drill steels or the like, a chamber, means for inserting the end of a steel into said chamber and for moving it lengthwise of said chamber, and means for-causing hot products of combustion to pass into said chamber along the line of travel of said steel and to flow lengthwise of both the steel and said chamber and to" be discharged from said chamber atone end thereof. Y

44. In a furnace, means providing a chamber, means to support the end of a drill steel or the like for movement along said chamber, means providing a chamber parallel to the first andseparated therefrom, means establishing communication between said chambers adjacent the upper portion of each, and a discharge outlet in communication with the lower portion of the first named chamber. 4

45. In a furnace, means providing a chamber, means to support the end of a drill steel or the like for movement along said chamber," means providing a chamber parallel to. the first and separated therefrom, means establishing communication between said chambers adjacent the upper portion of each, means for causing hot products of combustion to flow from one end of said second chamber in the direction of movement of said drill steel, and a discharge outlet for the second chamber.

46. In a furnace, means providing a chamber, means to support the end of a drill steel or the like for movement along said chamber, means providing a chamber parallel to the first and separated therefrom, means establishing communication between said chambers adjacent the upper portion of each, and .adischarge outlet for the first named chamber and located at the lower portion of the end thereof toward which the drill steel travels.

47. In a furnace, means providing a central chamber and side chambers, means establishing communication between theupper portion of each sidechamber and the upper portion of said central chamber,

means for causing the presence of hot products of combustion in the side chambers, a discharge at one end of said central cham ber, a slot through the top wall of said central chamber through which slot the ends of drill steels may be inserted, and means for moving said drill steels laterally for causing their ends to traverse said central chamber.

48. In a furnace, a chamber having a slot extending in the direction of its length for receiving the ends of drill steels or the like, means for supporting and moving said steels lengthwise of said chamber, a combustion chamber, a wall separating said chambers, means establishing communication between said chambers for passing hot products of combustion into said first chamber throughout the length thereof, and an outlet froursaid first named. chamlmr and so located as to cause the hot products of combustion to flow over said drill steels.

H). In a furnace, a chamber having a slot extending in the direction of its length for receiving the ends of drill steels or the like, means for supporting and moving said steels lengthwise of said chamber, a combustion chamber, a wall separating said chambers, a slot establishing communication between said chambers for passing hot products of eomlmstion into said first chamber throughout the length thereof, and an outlet from said first named chamber and so located as,

adapted to be inserted, means for causing said steels to travel lengthwise of said chamher, and.- means for causing hot products of combustlon to enter said chamber in the form of a substantially uninterrupted sheet and to flow transversely to said steels' ada ted to be inserted means for causin said steels to enter said chamber and remain therein for-a predetermined time moving from one end of said chamber to the other, and means for causinghot products of combustion to enter said chamber at the side thereof and to flow in the direction of travel of said steels and lengthwise of said steels toward their ends and to be discharged. from said chamber adjacent the end from which said steels are discharged.

52. In an apparatus of the character described, means forming a chamber into which the ends of drill steels or the like are adapted to be inserted, means for moving said steels lengthwise of said chamber and for removing said steels from said chamber automatically after a predetermined period 'following their entry, and means for causing hot products of combustion to enter said chamber in the form of a sheet extending substantially the full portion of the length of the furnace traversed by said steels, said means comprising a slot in a Wall of said chamber at one side of the line of traverse of said steels and a discharge opening from said chamber at that side of the line of traverse of said steels opposite said slot.

53. In a heat treating apparatus, a quenching fluid tank, means for placing the heated part of an article in one portion of said tank, and an inlet for quenching fluid located adjacent such portion and arranged to project quenching fluid against said heated part.

54. The method of heat treating a cutting tool which comprises heating the end portion of such tool, projecting cold quenching fluid on the cutting end while such portion is in a heated state and afterwards progressively cooling the portion of the tool back of the cutting end.

55. In a heat treating machine for drill steels, means for heating the end portions of said steels and for simultaneously subjecting the portions of said. steel adjacent to said end portions to a flow of air directed along saidsteels towards said end portions.

56. In a heat treating machine for drill steels, means "for heating the end portions of said steels and for simultaneously subjecting the portions of said steels adjacent to said end portions to a flow of air directed along said steels towards said end portions, and means for causing said steels to be subjected to said heating for a predetermined period.

57. The method of heat treating the bit end of a drill steel which comprises heating the said end, keeping the portion of said steel adjacent said end cool during said heating by subjecting it to a draft, of 0001 medium directed along said steel toward said heated portion, then immediately hardening the cutting end of said bit by immen sion in a cooling liquid of said cutting end only, and in finally quenching the remaining heated portion by gradually immersing said heated end in saidcooling liquid;

In testimo'ny whereof, I have signed my name to this specification.

GEORGE ii. GILMAN. 

